As is well known to those skilled in the art, olefins have heretofore been prepared by the thermal cracking of various hydrocarbon streams. The cracking operation may be conducted on a normally gaseous or normally liquid hydrocarbon charge; a common charge may be high boiling, normally liquid, hydrocarbon stream typified by a wax-containing stock.
In the thermal cracking of typical wax stocks at charge temperatures of 600.degree. F.-800.degree. F., say 680.degree. F.-740.degree. F., typically about 715.degree. F. and outlet temperatures of 1050.degree. F.-1250.degree. F., say 1120.degree. F.-1180.degree. F., typically about 1125.degree. F. and outlet pressures of about 10-50 psig, say 15-40, typically about 20 psig, it is found that the product of effluent gas may contain an undesirably high content of paraffins in addition to the desired olefin content. Presence of paraffin represents decreased efficiency of the process.
It is an object of this invention to provide a process for cracking a charge high boiling hydrocarbon. It is another object of this invention to provide a process for cracking a charge high boiling hydrocarbon to form a product olefin characterized by decreased content of paraffins. Other objects will be apparent to those skilled in the art.